Abstract: In order to further enhance the environmental adaptability of an airborne laser rangefinder in the full temperature range, the relationship between temperature and output power signal-to-noise ratio of a detector module was analyzed. The equation for the optimum multiplier factor and temperature was derived. The reasons for the deviation of the best avalanche multiplier factor caused by temperature change were expounded. According to linear temperature characteristics of the breakdown voltage of an avalanche detector, based on natural logarithm method, a linear temperature controlled circuit of the avalanche bias voltage was designed to compensate the multiplication factor due to temperature in the range of -55℃~70℃. Good test results were obtained with this method used in new airborne laser rangefinders.The experimental results show the measured temperature control coefficient of the avalanche bias voltage is 2.29V/℃ with an error of less than 4% relative to the theoretical coefficient. This method meets the special requirement for airborne environment.